Synthesis and characterization of water soluble self-passivated graphene quantum dots for biological applications

The excellent photoluminescent properties of graphene quantum dots (GQDs) makes them suitable candidates for biomedical applications, but their corrosion resistance has not been extensively studied. Here we report a detailed and systematic study of the luminescence and electrochemical behavior of GQDs. In the measured photoluminescence (PL) spectra, the emission peak is shown to be at ~455 nm. In addition, the good optical properties of the GQDs are attributed to the self-passivated layer onto the surface of the GQDs as revealed by electrochemical tests.